Releasable ski binding

ABSTRACT

A releasable ski binding with a locking element which during the release action of the binding retracts out of its holding position against spring force, this locking element being coupled with a displacement element. The displacement element immerses into a first of two compartments containing a fluid medium and communicating with one another by a throttle location. A first spring is coupled with the displacement element by means of the fluid medium in the first compartment and a second spring is coupled with the displacment element by means of the fluid medium in both compartments.

United States Patent Gertsch et al.

[Ill 3,888,498

i 51 June 10, 1975 35ll.l ll) lU/lifi'i Salomon ISO/11,551-

Primary Examiner-Robert R Song Attorney Agent, or Firm-Werner We Kleeman l57| ABSTRACT A releasable ski binding with a locking element which during the release action of the binding retracts out of its holding position against spring force, this locking element being coupled with a displacement element, The displacement element immerses into a first of two compartments containing a fluid medium and communicating with one another by a throttle location. A first spring is coupled with the displacement element by means of the fluid medium in the first compartment and a second spring is coupled with the displacement element by means of the fluid medium in both compartments.

17 Claims, 4 Drawing Figures mm ll mu Illli Illlll l llfi lllllll lll'r:

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PATENTEI] JUN l 0 I975 SHEET Fl I Figlr 'l'he present invention relates to new and improved constructions of safety ski bindings or releasable ski bindings.

fhe reliability of releasable ski bindings is dependent upon conditions which are in paradox with one another. namely upon conditions which are diametrically opposed to one another, n the one hand. the binding must give in the presence ofevternally acting forces in order to avoid injury to the skier. On the other hand. the binding must not give in the presence of externally acting forces so as to avoid faulty release of the binding. An absolutely reliable releasable ski binding therefore must be capable of differentiating between forces which can cause injury to the skier from non-dangerous forces.

Notwithstanding numerous efforts in this particular field of technology. it was not heretofore possible to completely fulfill these requirements. ln fact. it has been found that in the presence of impacts which act front the supporting surface or ground upon the ski and although of considerable magnitude still are not dangerous to the skier. provided that they do not result in the skier falling. oftentimes such forces or impacts nonetheless bring about faulty release of the binding. which then automatically causes the skier to fall even though such was not absolutely necessary. Due to such faulty release action of the binding. and which mostly surprises the skier. very serious injuries to the skier can arise. In order to prevent such injuries particularly in the case of skiers who ski at high speeds, and whose skiing technique automatically produces impact forces such skiers tend to set the bindings much harder than would be permissible in consideration of a positive release action of the binding. with the result that the binding tends to fail particularly under those conditions when it really should be most effective.

Now. to solve such problems there has been proposed in German patent publication 1,578,901. a binding which is equipped with a dampeningand/or delay mechanism. namely with a piston which displaces a liquid through a throttle opening. Such mechanism influences. although in a limited manner. the course of the release action as a function of time. namely insofar as the displacement of a predetermined liquid volume through the throttle opening and corresponding to the release action requires a predetermined minimum time span. In order to obtain the strived-for objective, the same must therefore then be calculated longer than the possible duration of the impacts which are to be expected. Under these circumstances it should be readily apparent that such binding only constitutes a compromise solution. A pronounced throttling would quite considerably reduce or in fact completely eliminate the danger of faulty release action of the binding. but at the same time would also impair the desired release action and thus. under circumstances. could place the same in doubt. Apart from the foregoing. the non-sensitivity of such binding with respect to impacts is proportional to the hardness of the resistance with which these bindings oppose impacts.

SUMMARY OF THE INVENTION Hence. it is a primary object of the present invention to provide an improved construction of releasable ski binding which is not associated with the aforementioned drawbacks and limitations of the prior art proposals.

Another and more specific object of the present in vention relates to an improved construction of releasable or safety ski binding which is relatively simple in construction and design. extremely reliable in operation. not readily subject to malfunction or breakdown. and provides for positive and reliable release action of the binding so as to prevent injury to the skier.

Now in order to implement these and still further objects of the invention. which will become more readily apparent as the description proceeds. the invention relates to a new and improved construction of releasable ski binding of the previously mentioned type. that is to say. a releasable ski binding with a locking element which during release of the binding retracts or returns out of its holding position against spring force, the locking element being coupled with a displacement element which immerses into a (first) of two compartments containing a fluid medium and which communicate with one another by means of a throttle location. According to one of the more significant objectives of this development. with such type binding avoiding faulty release of the binding should not occur due to the influence of the course of the release action as a function of time. rather by influencing the spring force as a function of the speed of the stroke. In order to solve this objective the invention contemplates coupling with the displacement element a first spring by means of the fluid medium in the first compartment and coupling with the displacement element a second spring by means of the fluid medium in both compartments.

Now. if with this constructional embodiment the locking element *slowly returns or retracts out of its holding position, namely within the time span required for the displacement of the corresponding quantity of liquid or fluid medium, then the displacement element can immerse into the first compartment. whereby through the agency of the fluid medium or liquid displaced in the second compartment the second spring is loaded. However. if there acts upon the locking element an increased" force. which strives to accelerate the displacement of the fluid medium or liquid out of the first compartment. but because of the (effective) throttling action however cannot be accelerated. then there does not arise a delay during retraction of the locking element. rather the locking element can give against the action of the first spring during each speed which. as a practical matter, comes under consideration. Basically. with such binding there is provided for a respective slow or a rapid return of the locking element selectively responsi e spring elements and accordingly there is realiied the possibility of differently calculating the spring force which is effective during the respective slow or rapid return movement of the locking element. This in effect means that an increased resiliently flexible holding force opposes the impacts. The function of the hydraulic system is to apply such increased holding force and as will become more fully apparent hereinafter to gradually decreasingly maintain such effective until there is a complete pressure equalization between both compartments Owing to this dual division or functionality of the spring force and the application of an increased holding force which can be exactly defined by the pre-bias of a spring. such type binding possesses a double characteristic. namely one for slower or longer lasting loads and another for rapid or shorter lasting loads respectively. Furthermore, both characteristics can be freely selected. so that there is no need for any compromise. Finally. and this point is also of extreme significance a release action always can momentarily occur because the binding is never and therefore also in the presence of extreme forces not (temporarily) blocked. Consequently, with such binding even when setting the same for extreme impacts, there is incipiently eliminated at stone-hard i.e. extremely hard reaction.

BRIEF DESCRlPTlON OF THE DRAWINGS The invention will be better understood and objects other than those set forth above. will become apparent when consideration is given to the following detailed description thereof. Such description makes reference to the annexed drawings wherein:

FIG. I is a longitudinal sectional view of a pneumatic locking mechanism for holding the front or rear end of a boot or a release plate at the ski;

FIG. 2 is a longitudinal sectional view of a further embodiment of pneumatic locking mechanism for holding the front or rear end of a boot or a release plate at the ski;

H0. 3 is a hydraulic mechanical variant embodiment of the invention; and

FIG. 4 is a further hydraulic mechanical embodiment of the invention DETAILED DESCRIPTION OF THE PREFERRED EMBODlMENTS Describing now the drawings, with the exemplary embodiment of releasable ski binding as depicted in FIG. I. the locking mechanism which has been designated in its entirety by reference numeral 1 comprises a cylindrical housing 2 in which there is retained for axial movement a locking element 3. For this purpose the locking element 3 embodies a guide portion or part 4 which is guided in piston-like manner within the housing 2. In the manner of a piston rod. a plunger 5 extends from such guide portion 4 into the housing 2, at the free end 5a of which there is suitably anchored the folded over portion 6 of a rolling bellows or diaphragm 7. In the locking element 3 there is provided an inlet valve mechanism 8 by means of which compressed air or a pressurized gas can be introduced into the interior of the rolling bellows or diaphragm 7. that is to say. into the compartment or chamber 9.

This compartment or chamber 9 is sealed by an intermediate wall 10 which carries at its side facing away from the rolling bellows or diaphragm 7 a sealing lip 11 which bears against the inner wall of the housing 2. In this manner there is formed a further compartment or chamber 12 which is connected with the compartment or chamber 9 by a calibrated throughput or throughpassage nozzle 13. This throughpassage nozzle 13 is located in an appropriate opening 10a of the wall 10 which together with the rolling bellows '7 and the sealing lip 11 is fabricated of one-piece from a rubber-like or elastomeric material. A regulating or adjusting screw 14 or equivalent structure, and which is sealingly guided through the end wall 2a of the housing 2, together with the nozzle 13, forms an adjustable throttle location.

The compartments 9 and 12 are filled with compressed air or with a pressurized gas, which provides a resilient resistance opposing the retraction or return of the locking element 3 in the housing 2 and through the agency of the locking element 3 directly or indirectly (for instance by using a release plate) exerts a resilient holding force upon the ski boot or the like. The magnitude of this holding force is thus apart from the rest condition dependent upon the speed with which the possibly encountered release action occurs, in other words the speed with which therefore the locking element 3 is pushed back into the housing. If this occurs slowly, then the increase of the pressure in the compartnient 9 is accompanied by an approximately uniform increase of the pressure in the (rear) conipartment [2, since during the time which is available there occurs, through the agency of the nozzle 13, a pressure equalization or balancing. If however. the locking element 3 is pushed back or retracted quicker, then the increase of the pressure in the compartment 9 precedes that in the compartment 12, so that until there is realized pressure equalization there prevails in the compartment 9 a higher pressure than such otherwise would correspond to the momentary position of the locking element (after pressure equalization). in other words, during slow stroke of the locking element, the entire enclosed gas volume functions as a (relatively soft) spring, whereas during rapid stroke and until there has occurred pressure equalization only the partial volume enclosed in the compartment 9 is effective as the spring (which at the start is hard). Conversely considered, such pneumatic cushioning or shock ab sorption provides a resistance for hard impacts which exceeds the holding force exerted statically or during slow stroke of the locking element. In this way it is possible to completely avoid faulty release action of the binding. Furthermore, the security or safety of the binding can be increased in that the binding can be adjusted to be softer than was heretofore conventional through the selection of a relatively low static holding force.

Now with the exemplary embodiment of releasable ski binding depicted in FIG. 2, the plunger, which in this case has been designated by reference character 51, is extended in length so as to pass through a central opening of the partition or intermediate wall 10 into the compartment or chamber 12. The regulation or adjusting screw. which has here been designated by reference character 141, in this case extends through the plunger 51 and cooperates with an equalization or balancing channel 15 provided at the plunger and which channel communicates with both compartments 9 and 12 respectively. The equalization or balancing channel 15 together with the annular or ring-shaped gap surrounding the plunger 51 and enclosed by the partition wall 10 forms the compensation or balancing connection. The filling valve 8 is located at the end wall 2a of the housing 2. The mode of operation of this embodiment is basically the same as that discussed above in conjunction with FIG. 1. One difference merely resides in the fact that the plunger in the compartment or chamber 12 tends to directly bring about an increase in pressure, which however with a certain retraction or return movement of the locking element 3 is smaller than that in the compartment 9, corresponding to the larger displacement volume of the rolling bellows or diaphragm 7.

The characteristic of such locking mechanism can be influenced in a number of different ways. Thus, for instance. the wall III of the embodiment of FIG. I can be constructed in a membrane-like or diaphragmdike manner and during a sudden stroke the nozzle 13 can retract in the direction of the. and it necessary. up to the regulating screw 14. so that the throttle location can be correspondingly restricted or in fact completely closed. What is decisive for the characteristic of such locking mechanism is furthermore of course also the volume of gas which is filled-in in relation to the volume of the compartments. wherein both factors can be changed. In particular. it is possible to provide measures in order to alter the volume of one or both compartments. for instance by changing the basic position of the plunger 5 or the length thereof. in similar mannor, the compartment 12 also could be closed by a roll' ing bellows or diaphragm which is adjustable by means of a plunger. The locking mechanism can be furthermore assembled together in building-block manner from interexchangeable elements which. depending upon the desired characteristic. can be assembled together.

Generally. it is therefore to be remarked that the problems which are associated with the adjustment with such locking mecahnism can be markedly simplified insofar as here apparently there is present a decisive step towards a unitary binding. This is so because the different behavior of the locking mechanism during a slow stroke and a surge-like stroke extensively renders superfluous an individual adjustment throughout wide limits. It is therefore conceivable to get by with a limited assortment. which perhaps encompasses two or three. in consideration of a predetermined characteristic, fixedly adjusted locking mechanisms. In so doing. it is possible to employ unitary anchoring components and exchangeable spring or locking elements respectively.

It should be understood that the described gas cushioning can be provided independently of the fact whether the actual locking element is supported to be displaceablc. pivotable or otherwise movable and correspondingly retracts.

The comments and observations which have been made in connection with the already disclosed embodiments are analogously applicable to the variant constructions depicted in FIGS. 3 and 4. With both of these variant embodiments of releasable ski binding there is provided a locking element which is constructed as a pivotal pin 33 and which. as is known. in this particular art. is intended to retain the front or rear end of a re lease plate or the ski boot at the ski. Against the rear of the locking element 33 there bears a piston 34 defining a displacement element and also like the collar 35 of the locking element 33, is guided in a cylindrical compartment or chamber 36 of a housing designated in its entirety by reference numeral 37. The compartment 36 communicates through the agency of a throttle opening 38 with a further cylindrical compartment or chamber 39 enclosed within the housing 37. In this additional cylindrical compartment 39 there is displaceably guided a piston 40 defining a further displacement element. The compartments 36 and 39 are filled with a suitable fluid medium. for instance an hydraulic fluid medium. which under the action of a spring 41 bearing at one end or face of the piston 40 is held under pressure. With this arrangement the collar 35 of the locking element 33 is pressed via the piston 34 towards the right against an annular or ring-shaped stop or abut ment 42 of a housing 43 in which there is displaccably guided the housing 37. The other end of the spring 41. with the embodiment depicted in FIG. 3. bears against an adjustment or regulating screw 44' and. with the embodiment depicted in FIG. 4. against an adjustment or regulating screw 44". The adjustment screw 44 in turn is located in a threaded bore 44a of an adjustment ring 45' defining a countersupport which is inserted into the internal threading 43a of the housing 43. The adjust ment screw 44" (FIG. 4 I. on the other hand. is inserted into the internal threading 37a of the housing 37. Corresponding to the adjustment ring 45' there is provided an adjustment ring 45" for the embodiment of FIG. 4. In both cases one end of a spring 46 bears against the corresponding countersupport. i.e. adjustment rings 45' and 45" respectively. which at the other respective end bear against the housing 37, in order to press the same against the stop 42 of the spring housing 43.

Now if the locking element 33 is slowly rocked or pivoted. then the liquid is displaced via the associated piston 34 out of the compartment 36 through the asso ciated throttle opening 38 into the compartment 39. whereby the force of the spring 41 must be overcome. This spring essentially fulfills the function of the release spring. However. if the rocking or pivoting ofthe locking element 33 occurs quicker than such would permit the flow of liquid out of the compartment 36 into the compartment 39. then the entire housing 37 is displaced towards the right. with the embodiment of FIG. 3 against the action of both telescopically inserted springs 46 and 41 respectively. with the embodiment of FIG, 4 on the other hand only against the action of the spring 46. Of course. associated therewith is the (relatively) slow displacement of the liquid out of the compartment 36 into the compartment 39, so that the spring 46 can gradually relax. whereby of course to the same extent the spring 41 is further stressed. With the variant embodiment of FIG. 4 the spring 46 is stronger than the spring 41. With the embodiment of FIG. 3 both of the springs 41 and 46 together of course provide a higher spring force than the spring 41 alone. In accordance with this arrangement. there is realized for both embodiments a release characteristic which is solely determined by the spring 41 and another diffen ent release characteristic which is determined by the coaction of the spring 46. Such can be determined independently of one another with the aid of the adjustment or regulating screws 44' and 44" respectively, as well as the adjustment rings 45' and 45" respectively. The result is that the binding in the presence of lower forces is opposed by a smaller resistance and in the presence of larger forces requiring rapid release is on posed by a resistance which at the beginning is greater. whereby when such larger forces continue to prevail the resistance gradually is only produced by the normal release spring. In so doing. the binding also responds to greater impacts in a resilient flexible manner and it is accordingly not blocked even during the time span re quired for pressure equalization between both compartments. Consequently. under this aspect. the effectiveness of the throttling is not subjected to any limits and. as mentioned. there exists the necessity of a compromise in this respect.

It should be understood that the intermediate wall separating both compartments 36 and 39. also with these embodiments, could be elastically resilient in order to initially increase the throttling action similar to HQ. 1. lt also would be possible to insert a movable element in the throttle opening 38. which is shifted or displaced out of its normal position as a function of the flow velocity in order to temporarily increase the effcctiveness of the throttling action. These measures basically do not serve the purpose of influencing as a function of time the release action. although they are suitable for delaying the pressure equalization between both compartments. in this case the purpose also resides in influencing the spring characteristic insofar as namely owing to a temporarily more pronounced throttling the spring 46 is correspondingly more markedly loaded and fo a longer time.

It should be understood that the hydraulic compo nent can be constructed as a mountable unit with or without spring 41 or locking element 33, and which advantageously is encapsulated. In this regard there are conceivable solutions which employ a rolling bellows or diaphragm and thus in their basic aspects corre spond to the embodiments according to FIGS. 1 and 2 previously discussed.

Also the embodiment according to FIGS. 3 and 4 belong in the category of a unitary binding. in analogous manner the indicated adjustment possibility for the springs 41 and 46 respectively is not to be considered as being an absolute necessity. In fact it is also conceiv able in this case that it is possible to get by with a mini mum assortment of springs. whereby an adjustment possibility can be dispensed with and a setting possibil ity (for instance with the aid of underlay or support disks) essentially only then would be used for compensating manufacturing tolerances.

While there is shown and described present preferred embodiments of the invention. it is to be distinctly understood that the invention is not limited thereto. but may be otherwise variously embodied and practiced within the scope of the following claims. ACCORD- INGLY.

What is claimed is:

l. A releasable ski binding comprising a housing means. a locking element which is displaced back against spring force during release out of its holding position mounted in said housing means, a displacement element. said locking element being operatively coupled with said displacement element. means for providing two compartments defining a first compartment and a second compartment containing a fluid medium. means providing a throttle location for flow communicating with one another said two compartments. said displacement element immersing into one of said two compartments. a first spring coupled with the displace ment element by means of the fluid medium in the first compartment and a second spring coupled with the dis placement element by means of the fluid medium in both compartments.

2. The releasable ski binding as defined in claim 1, wherein said compartments contain a gaseous fluid medium.

3. The releasable ski binding as defined in claim 1, wherein said first compartment embodies a movably supported housing, said housing being supported by means of the first spring against displacement under the action of the locking element.

4. The releasable ski binding as defined in claim 3, wherein the housing of the first compartment is displaceably guided in the displacement direction of the displacement clement engaging into such compare ment.

5. The releasable ski binding as defined in claim 4, wherein said second compartment is arranged within S the displace-able housing of the first compartment.

6. The releasable ski binding as defined in claim 5, wherein both of said compartments are arranged behind one another in the displacement direction of said housing which is common to both said compartments. and a second displacement element for delimiting the second compartment in such direction.

7. The releasable ski binding as defined in claim 6. wherein the first spring engages with the common hous ing and the second spring engages with the second dis placement element.

8. The releasable ski binding as defined in claim 7. wherein the second spring has an end which is supported at the common housing.

9. The releasable ski binding as defined in claim 8. wherein the second spring is weaker than the first spring.

10. The releasable ski binding as defined in claim 7, further including a countcrsupport which is stationary with respect to the common housing of the compartmerits. both ofsaid springs having a respective end supported at said stationary countersupport.

ll. The releasable ski binding as defined in claim 8, wherein the common housing of the compartments is displaceably guided in a spring housing defining said housing means.

12. The releasable ski binding as defined in claim 9, wherein the common housing of the compartments is displaceably guided in a spring housing defining said housing means.

13. The releasable ski binding as defined in claim 10, wherein the common housing of the compartments is displaceably guided in a spring housing defining said housing means.

14. The releasable ski binding as defined in claim 1 wherein said springs comprise helical springs which extend coaxially in the displacement direction of the dis placement element.

IS. The releasable ski binding as defined in claim 14, further including a spring housing defining said housing means and enclosing said springs, a selectively adjust' able countersupport defining a closure for said spring housing, and wherein said springs are telescopically inserted within one another and bear against said countersupport.

16. A releasable ski binding comprising a locking element which is displaced back against a resilient force during release out of its holding position, a displacement element with which said locking element is coupled. said displacement element immersing into one of two compartments containing a fluid medium and communicating with one another through the agency of a throttle location. the improvement comprising a first resilient means operatively coupled with the displacement element by means of the fluid medium in the first compartment and a second resilient means coupled with the displacement element by means of the fluid medium in both compartments.

1?. A releasable ski binding comprising housing means. a locking element which is displaced back against a resilient forced during release out of its holding position supported by said housing means. a displacement element. said locking element being opera- 10 of said two compartments, and wherein a first resilient force acts upon the displacement element by means of the fluid medium in the first compartment and a second resilient force acts upon the displacement element by means of the fluid medium in both compartments. 

1. A releasable ski binding comprising a housing means, a locking element which is displaced back against spring force during release out of its holding position mounted in said housing means, a displacement element, said locking element being operatively coupled with said displacement element, means for providing two compartments defining a first compartment and a second compartment containing a fluid medium, means providing a throttle location for flow communicating with one another said two compartments, said displacement element immersing into one of said two compartments, a first spring coupled with the displacement element by means of the fluid medium in the first compartment and a second spring coupled with the displacement element by means of the fluid medium in both compartments.
 2. The releasable ski binding as defined in claim 1, wherein said compartments contain a gaseous fluid medium.
 3. The releasable ski binding as defined in claim 1, wherein said first compartment embodies a movably supported housing, said housing being supported by means of the first spring against displacement under the action of the locking element.
 4. The releasable ski binding as defined in claim 3, wherein the housing of the first compartment is displaceably guided in the displacement direction of the displacement element engaging into such compartment.
 5. The releasable ski binding as defined in claim 4, wherein said second compartment is arranged within the displaceable housing of the first compartment.
 6. The releasable ski binding as defined in claim 5, wherein both of said compartments are arranged behind one another in the displacement direction of said housing which is common to both said compartments, and a second displacement element for delimiting the second compartment in such direction.
 7. The releasable ski binding as defined in claim 6, wherein the first spring engages with the common housing and the second spring engages with the second displacement element.
 8. The releasable ski binding as defined in claim 7, wherein the second spring has an end which is supported at the common housing.
 9. The releasable ski binding as defined in claim 8, wherein the second spring is weaker than the first spring.
 10. The releasable ski binding as defined in claim 7, further including a countersupport which is stationary with respect to the common housing of the compartments, both of said springs having a respective end supported at said stationary countersupport.
 11. The releasable ski binding as defined in claim 8, wherein the common housing of the compartments is displaceably guided in a spring housing defining said housing means.
 12. The releasable ski binding as defined in claim 9, wherein the common housing of the compartments is displaceably guided in a spring housing defining said housing means.
 13. The releasable ski binding as defined in claim 10, wherein the common housing of the compartments is displaceably guided in a spring housing defining said housing means.
 14. The releasable ski binding as defined in claim 1 wherein said springs comprise helical springs which extend coaxially in the displacement direction of the displacement element.
 15. The releasable ski binding as defined in claim 14, further including a spring housing defining said housing means and enclosing said springs, a selectively adjustable countersupport defining a closure for said spring housing, and wherein said springs are telescopically inserted within one another and bear against said countersupport.
 16. A releasable ski binding comprising a locking element which is displaced back against a resilient force during release out of its holding position, a displacement element with which said locking element is coupled, said displacement element immersing into one of two compartments containing a fluid medium and communicating with one another through the agency of a throttle location, the improvement comprising a first resilient means operatively coupled with the displacement element by means of the fluid medium in the first compartment and a second resilient means coupled with the displacement element by means of the fluid medium in both compartments.
 17. A releasable ski bindiNg comprising housing means, a locking element which is displaced back against a resilient forced during release out of its holding position supported by said housing means, a displacement element, said locking element being operatively coupled with said displacement element, means for forming two compartments comprising a first compartment and a second compartment each containing a fluid medium, means defining a throttle location for flow communicating said two compartments with one another, said displacement element immersing into one of said two compartments, and wherein a first resilient force acts upon the displacement element by means of the fluid medium in the first compartment and a second resilient force acts upon the displacement element by means of the fluid medium in both compartments. 